Cal Hypo for schocking

[S Ray]

Hi all, newbie here.
I am schocking with Cal Hypo (73%) because sand was falling from walls. (Years of 3 inch pucks).
Starting chems
FC 5
CC 0
PH 7.7
CH 260
CYA 45
TA 85
First I added 2 Lbs, FC to 15, added 1Lb, FC to 17, added 1 Lb, FC to 18, added 1 Lb, FC to 19, end of day one.
Early AM, FC is still at 19, added 1 Lb FC to 21, added 3 more Lbs thru out day to maintain FC at 20 or higher.
Early AM FC is still at 21 (no change from prev night) Switched to bleach. Maintained above 20.
I am near the end of third day and the shallow end, and the walls are still a light green. Should I contiue schocking?
I mixed the Cal Hypo in a large bucket befor adding to pool.
Thanks and what a great site.
Steve

 

[duraleigh]

Should I contiue schocking?

Yes, shocking is a process wherein you hold your FC up at shock level until....

1. Your pool water is sparkling
2. Your CC's are .5ppm or less
3. You can hold your FC overnight without losing more than 1ppm.

Stay with your FC up there until you meet all those conditions.....then you are done. (it sounds like you are close)

 

[frustratedpoolmom]

because sand was falling from walls. (Years of 3 inch pucks).

What does this mean?

Are you brushing the walls while the pool is at shock level? Use a brush appropriate for plaster pools.

FC holding overnight twice usually means the algae is dead....so something isn't quite right here.....

 

[S Ray]

Hi again.
Sand from walls means when I rub the walls with my hand I feel sand, and when i run the polaris the bag fills whith sand, and when I brush the pool (2 or 3 times a day during shocking) the filter cart is full of sand (no green). Also the pool surface is very rough. Could algae be in the holes hiding from the brush? (standard pool brush from Leslies).
Thanks, Steve

 

[frustratedpoolmom]

That kind of sounds like calcium scale....was your PH above 7.8 for any extended period?

Standard pool brush? Nylon, like for vinyl pools? You need one for plaster, a "combo" brush with stainless steel bristles, I believe. Stainless steel brushes are okay for plaster that is older than 1 year.

 

[S Ray]

Hi again.
The PH has been low for years because 3 inch pucks were used in a floater. I think thats why the sand is fallihg out of the walls. Negative SI. causing corrosion of plaster. I will look for a new brush tomorrow.
Thanks, Steve.

 

[frustratedpoolmom]

OOh....that whole CSI thing... I'm still learning about that. Well I'm wondering if this is more of a stain in the "sandy stuff" rather than live algae? Or is it possible that with all the crevices and what not from the rough surface the algae good get in there....If it is still alive the chlorine and brushing will take care of it.

Did you determine if your FC is holding overnight? (If you are brushing at shock level, and you leave the brush out to dry, there shouldn't be an algae in the brush that would then lead to this problem...)

 

[S Ray]

The FC is holding overnight. No CCs, and the water is clear. I rubed a 3 inch puck on the steps last night and today they are white, just what I wanted. Now to get to the walls at the deep end. Any thoughts? Also, will a new brush get into the holes in the plaster? How about a wire brush, I found one from the prev owner.
Thanks,Steve

 

[frustratedpoolmom]

Oh that's a good sign. It's probably just residual staining. You could try just brushing with the wire brush you found while the FC is elevated for a few days and see if that fades them. The alternative is what you did on the steps but that seems rather impractical doesn't it. Good luck.